Physical Properties of Polypeptide Electrospun Nanofiber Cell Culture Scaffolds on a Wettable Substrate

Abstract

Physical properties of poly(L-ornithine) (PLO), a polycation, poly(L-glutamic acid 4 -co-L-tyrosine) (PLEY), a polyanion, and electrospun fibers made of these polymers have been determined and compared. The polymers adopted random coil-like conformations in aqueous feedstocks at neutral pH and in dehydrated cast films and fibers on glass, and the fibers comprised numerous counterions, according to spectral analysis. Adsorption of model proteins and serum proteins onto hydrated and crosslinked fibers depended on the electrical charge of the proteins and the fibers. The surface charge density of the fibers will be comparable to, but less than, the charge density on the outer leaflet of the plasma membrane of usual eukaryotic cells. The present analysis thus advances understanding of cell behavior on electrospun fiber scaffolds, a topic of considerable current interest.

Mechanisms of Stability of Fibers Electrospun from Peptides with Ionized Side Chains

“…PLEY (20–50 kDa by viscometry) was synthesized in solution and obtained from Sigma (USA) as a lyophilized polydisperse salt. The polydispersity index was ≈1.1;16 polydispersity is rather unlikely to have influenced the present results. The counterions were Na + .…”

“…The nominal concentration of PLEY for electrospinning was 50% w/v, or 14 m M polymer. Fibers were prepared as described previously 15, 16. Briefly, polymer feedstock was taken up into a 1 mL syringe outfitted with a 0.5‐mm metallic blunt‐end needle (Jensen Global, USA).…”

“…Two model synthetic peptides for electrospinning research are co ‐poly( L ‐glutamic acid 4 , L ‐tyrosine 1 ) (PLEY) and poly( L ‐ornithine) 14, 15. Both are extensively ionized at neutral pH, both are mostly random coils in aqueous solution and fibers made of these polymers readily dissolve in water in the absence of covalent crosslinks 16…”

Review of digital holographic microscopy for three-dimensional profiling and tracking

“…The microfiber appeared curved and elongated, consistent with our previous work. 104 The field of view was 90 × 90 μm 2 with 464× 464 pixels. The hologram was then reconstructed from Z ¼ 100 to −100 μm, in −1-μm steps.…”

Gene delivery using dendrimer/pDNA complexes immobilized in electrospun fibers using the Layer-by-Layer technique

“…14 The basic electrospinning system consists of four parts, namely the syringe pump, a source of high voltage, a spinneret, and a grounded collector. 15 Figure 2 shows a schematic representation of an electrospinning machine. The syringe pump is used to pressurize the polymer solution in the syringe.…”